The present invention relates to a macerating wire assembly and to a method for macerating a thrombus.
Brain attack afflicts more than 700,000 people in the United States annually. About 70 to 85% of brain attack episodes are attributable to ischemic stroke, which carries a mortality of 15-33%. Emerging treatments for acute cerebral ischemia include thrombolytic treatment. One type of thrombolytic treatment involves an early use of clot lysing agents and a subsequent restoration of blood flow. One lysing agent, rt-PA has been shown to be effective in restoring circulation and in reducing the overall morbidity. However, the benefits of rt-PA are effective only if treatment begins within the first 90 minutes to 3 hours after the initial ictus.
Currently, trials are underway to reduce the complications associated with this treatment by using local intra-arterial versus systemic intravenous delivery as well as the potential use of other low cost alternative thrombolytic agents. There have also been advances in imaging technologies such as perfusion MRI, CT angiography, and advances in diagnostic blood tests all geared to the early diagnosis of stroke to speed treatment and expand the efficacy of these early interventions.
Other types of stroke treatment include early imaging, and a creation of dedicated stroke centers. All of these treatments have brought a greater emphasis the early treatment of stroke. A key to this treatment is a re-establishment of blood flow as early as possible to limit ischemic brain damage. The difficulty with thrombolysis alone is that this technique depends upon several variables, clot type, clot density, location, metabolism and so forth which adversely impact the effectiveness of this treatment.
Several devices have been designed for peripheral clot disruption. One device is described in U.S. Pat. No. 5,779,721 (xe2x80x2721), which issued Jul. 14, 1998. The ""721 patent describes a system for opening a lumen in an occluded blood vessel. The system includes a working head for revascularizing the blood vessel and a mechanism for extracting or removing debris produced by operation of the working head. The working head is a rotary impacting impeller. The mechanism for extracting or removing debris introduces an infusate liquid into the blood vessel adjacent the working head and withdraws the liquid and some blood from the vessel. The infusate liquid may include a lytic drug such as heparin or urokinase. The blood and infusate liquid are remotely collected.
Thrombectomy devices may be utilized as a part of the system. One device is the Amplatz Thrombectomy Device designated by the trademark CLOT BUSTER by Microvena Corporation. Another device is the Craig Thrombectomy Brush.
One embodiment of the present invention includes a clot disrupting wire/catheter assembly. The clot disrupting wire/catheter assembly comprises an annular sleeve and a core wire that is positioned within the annular sleeve. A distal end wire is attached to the annular sleeve and the core wire.
Another embodiment of the present invention includes a method for clot disruption. The method comprises providing a clot disrupting assembly that comprises an annular sleeve, a core wire positioned within the annular sleeve and a distal end wire attached to the annular sleeve and the core wire. The method also includes pushing the core wire in order to deploy the distal end wire and positioning the distal end wire within a clot. Another method embodiment includes pulling the core wire in order to deploy the distal end wire and positioning the distal end wire within a clot.
One other embodiment of the present invention includes a kit for clot disruption. The kit comprises a main body defining a first lumen and a second lumen and a clot disrupting assembly positioned within or is integral with the first lumen. A lytic drug may be enclosed in the second lumen.